So, on this site I hit "refresh" until I get to a puzzle that has a <30% success rate. I'm pretty sure I've done all of them and the challenge is gone. . .so, I was wondering if any of you know of any other logic sites that may present harder challenges? Maybe 6x6 or larger grids or clues that require more 'logical pathways' to be examined? If so, please share.

There are 5 houses each with a different color. Their owners, each with a unique heritage, drinks a certain type of beverage, smokes a certain brand of cigarette, and keeps a certain variety of pet. None of the owners have the same variety of pet, smoke the same brand of cigarette or drink the same beverage.

Clues:

The Brit lives in the red house.
The Swede keeps dogs as pets.
The Dane drinks tea.
Looking from in front, the green house is just to the left of the white house.
The green house's owner drinks coffee.
The person who smokes Pall Malls raises birds.
The owner of the yellow house smokes Dunhill.
The man living in the center house drinks milk.
The Norwegian lives in the leftmost house.
The man who smokes Blends lives next to the one who keeps cats.
The man who keeps a horse lives next to the man who smokes Dunhill.
The owner who smokes Bluemasters also drinks beer.
The German smokes Prince.
The Norwegian lives next to the blue house.
The man who smokes Blends has a neighbor who drinks water.

Thank you for that puzzle - it was fun. I ended up doing a 5x6 grid to keep track of stuff. While not necessarily 'harder' than the puzzles here and at puzzles.com, it was refreshing and the added twist was exactly what I was looking for.

Hopefully the powers at this website come up with a new logic engine that will add a fresh, different logic path or two the mix.